


Holy Trinity

by SpyroForLife



Series: To Please a God [2]
Category: Gravity Falls
Genre: Anal Sex, BillDip, Biting, Blow Jobs, Dirty Talk, Eating out, F/M, God Bill Cipher, Grinding, Hand Jobs, M/M, MaBillDip, Mabill, Nipple Play, Oral Sex, Praise Kink, Riding, Rimming, Scratching, Sibling Incest, Snuggling, Strip Tease, Threesome, Threesome - F/M/M, Vaginal Fingering, Vaginal Sex, Voyeurism, pinecest - Freeform
Language: English
Status: Completed
Published: 2016-01-31
Updated: 2016-01-31
Packaged: 2018-05-17 12:03:33
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 6,577
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/5868709
Author URL: https://archiveofourown.org/users/SpyroForLife/pseuds/SpyroForLife
Summary: <blockquote class="userstuff">
              <p>Sequel to "Tribute". One day, the god Bill Cipher invites to his home not just Mabel, but Dipper as well. Why should a god care what humans find immoral? The twins are nervous, of course, but they are devoted to him. So they will do whatever he asks of them.</p>
            </blockquote>





	Holy Trinity

Mabel was happy to tell Dipper about her encounter with their god. She didn't really mention how she had spoken so sarcastically to the being, instead going on about how focused he was, how he gave her exactly what she wanted and it was such a great experience. Dipper was happy for her, telling her that maybe he'll invite her back again.

Sure enough, Bill did. Many times. Each time starting out demanding, trying to make her listen to him, and then giving in to her humor, and allowing her to tease him. And he would dote on her, give her praise instead, something that was unusual but enjoyable for both of them. Mabel liked seeing the powerful god so reliant on her. And Bill liked being the one to worship for once, instead of being worshiped. It was so taboo that every time he gave her a compliment and she asked for more, it made him even more aroused. He was so thrilled that she had introduced him to this.

Of course Bill also still had Dipper visit him as well. And other humans, surely, though he has professed his fondness for the twins multiple times. But he stopped comparing them, something each of the Pines appreciated. Foreplay was really awkward when your partner has also fucked your sibling.

But Bill had no concept of immorality, or if he did, he didn't really care. So it wasn't that surprising when he asked both twins to join him the same night.

Dipper and Mabel were shocked. They had questioned him, but he didn't elaborate, just telling them to come to his palace at once. So the two had headed out at once. They gave each other nervous glances, making small talk, wondering if maybe Bill just wanted to have dinner with them. Not likely. But neither admitted out loud what was going to happen.

Each twin thought about the other, though. Neither found their sibling unattractive. Mabel could admire Dipper's strong jaw and thick brown hair, his dark and intelligent eyes. Likewise, Dipper has always liked Mabel's plump, rosy cheeks and sparkling caramel eyes, the curls of hair that cascaded down her back, nearly always ending halfway down it. But thinking about each other that way wasn't right, and so they chose not to. Now, however, it was all that was on their minds.

They seemed to make it to Bill's home in no time at all, and navigated to his throne room without needing any guidance. He wasn't in there. Which meant only one thing.

Mabel swallowed, and Dipper cast her a reassuring glance. “It'll be fine. Come on.” He held his hand out to her. She took it, letting him lead her as they made their way to the grand bedroom instead.

“D-Dipper, you don't think he's gonna make us...”

Dipper's expression was worried, but determined. “I don't know. But whatever he wants of us, I will obey him.”

Mabel frowned. Dipper was still so obedient to the god. Did he know that Bill liked being challenged? Or was he just used to submission so he didn't even question it by now? She supposed she would find out what he was like, if her suspicions were true...

They entered Bill's room. The light was dim except for some spots where black candles burned with blue flame, and the air was thick with the smell of... pine? Was that some kind of joke?

The god laid on his side on the bed, clad in a silk gold robe, eyelids lowered as he watched them.

“So glad you could join me,” he said with a grin, showing his sharp teeth.

“My god, you know I am your humble servant, pleased to answer your every whim,” Dipper replied, bowing his head. Mabel rolled her eyes.

“Glad to be here,” she said simply. Dipper glanced at her.

Bill's smile widened, and he turned to sit up, beckoning to them with a good four of his six arms. “Come, join me.”

Dipper hesitated, so Mabel decided to get to the point. “Bill, did you call us both here tonight so you could fuck both of us?”

Her twin audibly gasped, and Bill's eyes twinkled with amusement.

“Mabel, you can't talk to him like that,” Dipper said in a hushed voice.

“I just did, didn't I?” she replied.

He seemed like he wanted to admonish her, but Bill began laughing. “Oh Mabes, my beautiful star, I love how bold you are. Well, since you asked, yes. I do want to have both of you. I've had so much fun with you separately, I figured having both of you would double that fun!”

Dipper let out a surprised squeak, and Mabel said, “Bill, I know you probably don't care, but to humans that's kinda... fucked up.”

“Yeah, yeah, I know how iffy you humans get about the whole incest thing...” Bill did quotations with two hands. “I really don't give a shit. You're related. Big whoop. Get over here.”

Dipper hurried over with no questions asked, and allowed Bill to pull him up onto his lap, the god already hooking a leather collar around his neck and giving it a tug. Mabel didn't really care for it, but it seemed her brother was into it, because he was already blushing.

“You too, Mabel,” Bill said.

Mabel walked over to the bed. It only took a gesture from him for her to climb up too. He spread his legs out a bit, seating her on his lap as well. His arms wrapped around them, holding them close.

“Two gorgeous humans in my bed, I am one lucky god,” Bill hummed. His hands were already slipping under their clothes, stroking their skin. “This should be fun.”

“My lord, I'm not so sure I'm comfortable with this,” Dipper said. “Mabel is my sister, I can't... I mean, it's just not...”

“It's not socially acceptable. Yeah. I don't care. I'm fine with it. You're both adults and you can consent to whatever you want. Are you really telling me no, Dipper?” Bill slid a finger under Dipper's collar and gave it a yank. Dipper gasped, eyes falling shut.

“N-no, master. I'll do as you ask.”

“Good.” Appeased, Bill let go of him. He looked over at Mabel, taking hold of her hair and tugging her head back. “You, on the other hand, will probably need some convincing. Are you against this?”

“I... I don't really _want_ to do anything sexual with my brother, but if you command it, then...” She sighed. “I'm not going to fight you.”

Bill seemed surprised. “Well, all right, then. Good. I'm glad you're both so open-minded and devoted to me.” He casually pushed them back. “Now get up and strip for me. Make it sexy.”

They got up and moved a short distance away, looking at each other, and then back at him. Dipper was the first to start, slowly gyrating his hips as he slid his hands up the inside of his shirt, pushing it up. As his chest was exposed, one thumb brushed over a nipple, and he sighed out before tugging the shirt off entirely and dropping it.

Bill rested a pair of elbows on his knees, already leaning forward with interest.

Not to be outdone, Mabel scoffed and puffed out her chest, giving a graceful twirl and running her hands up through her hair, tossing it so that it fanned out before grasping her sweater (she had long since learned that Bill liked seeing her in them) and pulling it off in a fast motion. She swung her hair out of it and gave the garment a few twists, sliding it around her body and under her breasts as though drying herself off after a shower, hips swaying in their own sensual manner. She dropped it and adjusted her bra, and looked at Bill to see him grinning, clearly enjoying himself. He untied his robe, letting it slip open as he casually crossed a leg over the other.

Dipper scowled at his sister, blushing at her shameless display. He really couldn't deny how good she looked. Plump and shapely, nice breasts and large hips... he looked away, eyes on Bill as he continued moving his body to a silent beat, dancing a bit as he stepped out of his shoes and raised his feet to pull his socks off. Mabel did the same, mirroring him and humming quietly. He found himself following her tune. The woman was suddenly in his space, hands running down his arms, before gripping one wrist with a hand and spinning so her back was against his front, now grabbing his other wrist and placing his hands on her hips as she grinded against him.

“Mabel?” he yelped, shocked. Her skin was warm and he could smell her strawberry shampoo, they were nearly the same height so her hair was right there in front of his face... despite himself, he inhaled deeply, rubbing his nose against it.

“Don't be so tense, bro-bro,” she said playfully. “The god wants us to entertain him. He chose both of us for a reason. Let's not be strangers.”

“I... I ah...” His fingers curled, willingly grasping her hips. What was he doing? Why did this feel so right? “Okay.”

She smiled and looked over at Bill, who was watching with rapt attention, pupils dilated. She winked at him and continued to grind back against her brother, enjoying how his toned chest pressed to her back. As she rubbed her butt particularly hard against his groin, she felt a responding firmness. He made a choking sound, and she looked back to see him with his eyes closed, shame on his features.

“Aw, Dipper,” she cooed, letting go of his wrists and turning around to embrace him, though they didn't stop moving. “It's all right.”

“This is so wrong,” he muttered.

“It'll be our little secret, hm? Try not to overthink it.” She dropped her hands to his pants, opening them and pulling the zipper down all the way. He breathed in slowly, then nodded, shaking hands pushing his pants down completely.

Mabel skipped back, cheeks flushed as she wiggled her skirt down and took it off. She twirled it around an arm, and then threw it at Dipper. It hit him in the face, and he batted it aside, ears turning red. He kicked his pants off and went to stand next to her, both looking at Bill.

“There's my precious Pines, you're both so gorgeous,” the god said happily. “Come here, my loves.”

They returned to the bed, and he wrapped three arms around each of them, lifting them and spinning to pin them down on their backs below him.

“Look at you,” he said, stroking their faces, his middle hands sliding down their bellies, while the third pair gripped their thighs. “So wonderful, so devoted to serving me that you would put aside your own sense of morality to please me.”

“Of course, Master,” Dipper said earnestly. “Anything for you.”

“I mean I guess it's not so bad, at least Dipper is someone I know,” Mabel replied. “This is still weird though.”

“Mhm, you probably won't be thinking that for long.” Bill leaned down, kissing first Dipper, and then Mabel. They shifted to get closer to him, pressing up against each other too, a touch that made their hearts race and skin tingle. The two kept making eye contact, watching intently when one was being kissed by the god, a strange tension crackling between them.

Finally, it got to be too much. When Bill leaned back to just admire them, Dipper turned and cupped Mabel's face with both hands, tilting her head and kissing her. A jolt went through her body, and she gasped, recoiling a bit. He gripped tighter, nearly sobbing as he pressed their lips together. Her heart ached, and she responded, hands squeezing his shoulders as she leaned in. It felt good. He had talent, and somehow this felt right. It felt like something they've been needing to do for a very long time and hadn't realized until now.

Mabel rolled onto her side, throwing a leg over Dipper's hip and pulling him against her, aware of how turned on he was. His hips twitched, groin pressing just slightly against hers before Dipper jerked away, eyes wide. “M-Mabel, I'm sorry, I-”

“Shush.” She put her hand over his mouth. “It's okay. I'm enjoying this.”

“I am too,” he admitted, voice muffled. He licked her palm, and she let go. “I just... this is so...” He sighed, eyes watering. “It still feels so wrong.”

Mabel caressed his cheek, running her hand through his hair. Her brother really was sweet. So caring, not wanting to hurt her. Afraid that he was going to offend her, that this was going to ruin their relationship. She could tell all this because she was feeling it too. “Maybe it is wrong,” she said. “But you know what? I don't care. Let's just relax and have fun, okay?”

He leaned into the touch. “Okay.”

Bill licked his lips. “My, you two are absolutely sinful. I love it.” His hands had never really left their bodies, but now he put more attention into his stroking, along their legs and up their stomachs and chests, taking Mabel's bra off and then teasing their nipples. Both were equally responsive, Mabel a little more so, and Bill soon leaned over toward her, dropping his head to run his tongue over one of the sensitive buds. He squeezed her breast as he did, and she let out a low moan. Dipper moved to press his mouth to hers, and she shivered with pleasure. Her right arm, which has so far been pinned between their bodies, moved, hand finding his crotch and brushing over his erection. He groaned and grinded into the touch, and when he broke away to breathe, she grabbed.

“Gh. Mabel!” He almost wanted to push her hand away. But he didn't. He just laid there, and let her feel him through his underwear, stroking and coaxing him into full hardness. He whined, and she smiled.

“You're so cute, bro,” she teased.

Bill switched to suckle on Mabel's other nipple, and she moaned, back lifting. The god smirked, and slipped a hand up the inside of her thigh, palming gently between her legs. She was wet, and he pressed his thumb to where he knew her clit was, pleased with the way she shuddered. “I think you're ready,” he murmured, lifting his head and licking a trail up to her chin. He was also teasing Dipper, feeling along the head of his cock, which was straining against his boxers, already leaving a wet spot. “You both are.”

“Yes master, please, I'm ready to serve you,” he gasped out.

“I know you are. And you, Mabel?”

“I'm ready for whatever you got, my god,” she replied.

“Can you be a little more respectful?” Dipper shot at her.

“Oh, calm down, he likes when I talk to him like that,” she replied.

“He's our god, you can't just chat with him like he's our friend...”

“Well I think of him as my friend,” she declared. She leaned up to kiss Bill's nose, and then nuzzled him. “Well come on, tell me what you want us to do.”

“Hm... I'm feeling pretty naughty today.” Bill shrugged his robe off, letting it fall to the side. His cock was hard, dripping, and he ran a loose fist over it. “Dipper, roll over on top of your sister. Grind on her as you take your underwear off. Mabel, you get yours off too, and make sure you leave plenty of bites and scratches on him. I'll give you more orders once you're naked.”

The two were unsure, but they listened.

“You're so fucked up,” Mabel said to the god, before pulling Dipper on top of her, determined to make up for his hesitance. She did as told and dug her nails into his back, not surprised when he moaned and grinded against her. Damn, that felt better than it should. So much of this felt good. She rubbed against him, easing him into things, and soon he moved on his own, sliding his underwear down. His erection bobbed out, hot and hard, pressing against his belly. She took advantage of his pause to pull her own underwear off, and once the two had tossed them aside, she wrapped her legs around his hips and rolled against him just right, feeling the length of his cock slide against her entrance.

The two moaned, hips twitching at the unfamiliar but wonderful contact. Mabel leaned over to glance around Dipper's shoulder, and the man looked back too, waiting for instructions from Bill.

The god was pumping himself, mouth open slightly as he panted. His tongue licked over the corner of his lips. “Keep going. Grind yourselves together, get used to each other, touch. You both look so good.”

“I suppose we should put on a good show for him,” Mabel mused. She seized Dipper's collar in a hand, dragging him down and kissing underneath his jaw. She rocked her hips up, and he turned out to be surprisingly submissive to her, following her lead and pushing his down and forward. She was growing wetter at the constant friction, and soon got bold, giving him what he wanted and nipping at his skin. She couldn't get most of his neck because of the collar, but she bit what she could, both hands scratching his back. One of his hands was braced next to her, but the other was tangled in her hair, stroking, occasionally tugging as they got a particularly good grind in.

She was getting intimate with her brother, she thought. Really, she had been trying not to think about it too much, but now that she was... it made it seem better, somehow. It was taboo, it was gross, it was... exciting. He was so attractive, so strong but also so careful with her, reverent almost. And to think that she was grinding with him, digging her teeth and nails into his skin and giving him pleasure, while their powerful god watched over them and jerked off to the sight of them... this was hotter than anything she's ever done.

They were really starting to get into it when Bill suddenly said, “Stop.”

Dipper froze. Mabel huffed but also paused, meeting the other's golden eyes. They were large, full of lust.

“Okay. Listen up.” Bill leaned over Dipper, pressing along his backside and murmuring into his ear. It was almost too much for the man, and he rubbed against Mabel a bit. “I said stop.” Dipper stilled. “You have done excellent with keeping an open mind so far. Now... I want you to fuck her.”

The twins both went rigid.

“Y-you want me to... Master, I...” Dipper stared at Mabel, then back over his shoulder at Bill. “I don't think...”

“So stop thinking. Look forward.” Bill grabbed his face, turning it and making him look down. “Look at her. Look at your sister, laying underneath you. Breathing hard, cheeks red. Beautiful and ready and _willing._  You love her. You would do anything for her. You want to feel yourself sheathed inside her.” His voiced lowered, and Dipper whimpered. “I think she wants to feel you inside her too.”

“Mabel?” Dipper asked tentatively. “Do you want...”

“Yes,” she replied instantly. “Yes, let's do it, let's give Bill a show he won't soon forget.”

Dipper was really nervous, but he could feel Bill's intense gaze on his back, and he didn't want to upset him. He moved his hips back, and his fingers briefly felt along her folds, sliding between them. He's never done this before, he wanted to make sure he did it right. He pressed a finger inside, finding that there was little resistance. She was slick and warm around him, muscles seeming to squeeze before loosening. He breathed a little more quickly.

“You don't need to stretch it or anything, just go,” she said, laughing a bit.

“I knew that,” Dipper said defensively, pulling his finger out. He lined himself up, and slowly pushed his tip inside. It took a bit of effort, a bit of shifting as he got used to the way she felt, but then he was burying inside, and both of them called out.

“Fuck, Dip,” she exhaled, staring up at nothing. Then she focused on him. “Eager, huh?”

“Sorry.”

“Don't be.” She rested her arms around his neck, forehead leaning against his. She could feel his breath against her face. He was pressed so close to her. Perfect. “Have you been inside Bill before?”

“No.”

“Then this is probably new to you. Take your time, and just do what feels right. And make sure you pay attention to your body's signals. If you come inside me, I swear to god I will kill you.”

“Permission granted,” Bill chirped.

Dipper chuckled, and began to move. Tentatively at first, then more quickly. The other felt so good around him, hot and tight, but not so tight it was uncomfortable. He seemed to fit just right.

“S-so you don't like being come in, huh?” he asked.

“No, I don't want to get pregnant,” she said blankly.

“Oh. Right. That isn't even a concern for me so I didn't think...”

“Of course not. Now ssh, no talking, just... move.” She closed her eyes, enjoying the firm thrusts inside her, slipping past her sweet spot and making her squirm with pleasure. He wasn't as big as Bill, but he felt great nonetheless. He was a little clumsy, but it was charming, somehow.

Bill was breathing shallowly as he watched. His two favorite disciples were fucking each other, right here in his bed. He had told them to do this, and they were. To please him, and to fulfill their own carnal desires. He stroked his hard length, biting his lip. He wanted to be inside one of them. They looked good but they would feel even better, this could be so filthy and so _fun..._ He crouched down behind Dipper, two hands gripping the human's ass and rubbing it, smacking lightly. He moaned and thrust harder into Mabel, whose resulting keen sent another bolt of heat right to Bill's dick. He loved her voice so much.

“Don't stop,” Bill ordered, before spreading Dipper's cheeks and running his tongue along the cleft. Of course, Dipper's rhythm faltered, a startled noise escaping him. He gave him a harder slap. “What did I just say? Keep moving.” He did so, and the tips of Bill's tongue circled the human's hole, teasing and prodding. His saliva dripped down and pooled against the skin, soon allowing him to press his tongue inside.

“Master, I... I'm close,” Dipper whimpered. His movements only caused him to press himself harder onto Bill's tongue, and the slimy wet feeling inside him had him groaning.

“You're not finishing,” Bill said. “Not yet. Slow down if you have to, but you're going to hold out.”

Dipper slowed his pace a bit, legs shaking at the hot numbness overtaking them. He kept his eyes shut, leaning heavily on his elbows as Bill's tongue pressed deeper every time his hips jerked back. Mabel's panting felt so good against his shoulder, as did her nails in his skin, and he was kissing the side of her head, trailing his lips through her hair, just wanting to touch her, give her body the worship it deserved.

Bill worked his tongue in and out, getting Dipper nice and relaxed, lubricated and ready. This would still be a bit rough, but the human was a masochist. The god pulled his face back, rubbed some saliva onto his cock, and stood up on his knees, thrusting into Dipper in one fluid motion.

“G-god!” Dipper's back arched, hips snapping against Mabel's, all three crying out.

“Yes?” Bill asked with a smirk.

Dipper chewed his lip, adjusting to the feel of his god inside him and his sister around him. It was so much sensation at once, he felt like he might just go mad.

“Don't dawdle, keep going. I'll do my own thing.”

Dipper resumed, thrusting short and hard into Mabel, who easily responded to his rhythm. She kept peeking up at Bill, and at her brother's face. Dipper looked so wonderful right now, the way his body was being jerked back and forth between them, how his brow creased and his mouth gaped open, the desperate pleas his mouth formed but he couldn't find the words to actually say...

The heat in her body grew, reaching a fever pitch that had sweat breaking out on her skin, the tightness between her legs wound tighter and she began to squeeze around him, so close, and Bill's thrusts inside him were only pushing him deeper into her...

“Dipper!” she called, orgasm hitting her. She shivered and tightened her legs on either side of him, muscles contracting in waves around his cock.

The sensation was an utter surprise for Dipper, and that combined with Bill's thrusts against his sweet spot was more than enough to push him over the edge. He struggled to pull back from Mabel, and she loosened her hold, allowing him to pull out just in time to come. He moaned loudly as he did, arms quivering, barely managing to hold him up.

“Nngh, god...” Dipper slurred, body jumping with overstimulation as Bill continued to pound into him.

“You feel good, Dipper,” Bill praised. “You did so fucking good, great job.”

Dipper grunted out a thanks, tired. He opened an eye, meeting Mabel's flushed gaze. “You all right?” he asked her.

“Never been better,” she replied, entranced by his expression. She supported him until Bill finished and pulled out.

“Mm, fantastic,” Bill sighed, smiling at them both as he flopped down next to them, stretching out and idly scratching his stomach. “You two were so great. That was hotter than anything I've seen in a long time. It's one thing to make two mortals fuck for my amusement, but for two who already had such an intimate bond to do it? Man, that was great. Thank you.”

“You're welcome, Master,” Dipper replied, sighing as he let himself relax, draping himself in Mabel's arms. She petted his hair.

“You're so submissive,” she giggled.

“I've trained him well,” Bill laughed. “That's what I was expecting you to be like, but you pleasantly surprised me. It's good, though. I like having such different personalities in bed with me.” He closed his eyes, relaxing. “Mm, you two talk about whatever, I'm gonna chill until I'm ready to go again.”

“Again?” Mabel asked.

“Yeah, I'm not letting you guys go that easily! I'm having both of you again.”

“Fine by me,” Mabel said with a shrug. She looked at Dipper. “Hey, listen up. You gotta learn to take charge.”

“What do you mean?” Dipper asked.

“Exactly what I said. You let Bill push you around and tell you what to do. You have to stand up for yourself. Tell him no. Push back. He's so into it.”

“Are you sure?”

“Look, I've fucked him several times before this, I know what he's like. He likes obedience, sure, but defiance excites him. He likes not having to make all the decisions. It turns him on being told what to do. He may be a god but he knows how to relax and have fun. And letting weak mortals have some control over him feels so wrong that it gets him off faster than anything else.”

Dipper scoffed lightly. “Seems he's into a lot of things that are wrong...” He glanced over at Bill, but the other was just humming to himself, apparently tuning them out as he got lost in his own musings.

“I'm not surprised, honestly.” Mabel shifted a bit, putting both of them on their sides and snuggling close. “I liked this, though. You were... really good.”

“Yeah? Heh, you were good too.” He gently kissed her forehead. “This doesn't change anything, does it?”

“Nah. We've been together for so long, gotten to know each other so well... I guess this wasn't too much of a leap for our relationship. Besides we've both been having sex with the same guy, which means we might as well have been having sex with each other before this.”

“I don't think it works that way.”

“Eh.” She shrugged a shoulder. “Hey, he wants to go again, right? Well I think I have an idea, but it requires you to get a bit of confidence, and stand up to him, okay?”

“I don't know...” Dipper glanced at Bill, and then rubbed at his collar. He fidgeted with the leather, the reminder that right now, he was owned. The reminder that Mabel didn't have.

“I think you want to. Actually, I think you need to. It'll be simple. We're just gonna...” She leaned in to whisper the plan into his ear. As he listened, Dipper's eyes widened, darting at Bill several times. When Mabel finished, he stared at her for a good several moments.

“He would kill us,” he said.

“I don't think he would. I think he'd like it. Time to stand up for yourself, all right? Look, I'll lead. You'll see, he'll be into it.” She pulled out of his grip and crawled over to Bill, swinging up to straddle his chest and using her knees to pin down two of his arms. His eyes immediately opened, surprised and curious.

“Mabel, what are you doing?” he questioned.

“You,” she replied, crouching and kissing him. He purred as he responded, his free arms casually stroking her back and over her rear.

“What a treat,” he murmured, and she pecked at his cheeks and eyelids too, before gesturing at Dipper.

Dipper was nervous, but part of him has always wanted to take charge over the other, and now he had his chance. He moved to kneel between Bill's legs, taking his cock in his hands and gently stroking. It was soft, but quickly grew hard at the attention.

Bill moaned through clenched teeth. “Oh, you've got my loyal subject taking dominance over me now? Mabel, you naughty girl.”

“I sure am,” she sassed, sliding her hand behind her and finding one of Bill's nipples, giving it a squeeze. She knew she could be rough with him, and she was, twisting and tugging on the nub. He moaned, responding to Dipper now, rocking his hips. Dipper was very experienced in hand jobs by now, and it seemed he was giving Bill his absolute best. The god was so into this.

“I could throw both of you off with a thought,” Bill informed them, sighing out as heat and pleasure filled his being. “But I won't. I'm enjoying this too much. Do as you like.”

Mabel gave Dipper an “I-told-you-so” smile and pressed her lips to Bill's, making out with him. He responded eagerly, tongue tracing along her lips, which made her recoil a bit as she thought about where it just was. Bill clearly didn't find anything gross about it, but he respected that she didn't want it in her mouth, so the kiss didn't get any deeper.

“I can make any bacteria on my tongue vanish, you know,” he said to her once she paused for breath. “God and all.”

“Do it,” she said. He obeyed, and Dipper made a stifled gasp. “See, Dipper? He'll listen.”

“M-Master... er, Bill,” Dipper said firmly. Bill raised a brow. “Spread your legs.”

Bill opened them wider, and Dipper looked at his sister with awe. Then, feeling more confident, he leaned down and ran his tongue up Bill's shaft, before taking it into his mouth and sucking.

“Ah, Dipper, that's the stuff...” Bill encouraged, gripping Dipper's hair and tugging him down. He didn't set the pace though, wanting to see if Dipper did it on his own. And he did, and it was great. Bill liked not having to give them any orders. All he had to do was lay here and they would pleasure him. Humans were so great. But all too soon, Dipper was leaning back. “Stopping so soon?”

“I have a better idea,” Dipper replied, climbing up onto his lap. He spread Bill's thighs apart himself, a motion that made arousal curl hot in the god's gut. Then he took Bill's cock inside him, burying it to the hilt in one strong move.

Bill jerked his hips up, a loud grunt escaping him. Fuck, did he love when the human rode him. Usually he had to order him to, but now he was doing it on his own, and that was just so hot...

“Move,” he barked at him.

Dipper did so, easing himself up and down his length, hard and rough. Bill rolled his hips up to meet him, gripping his thighs hard enough to bruise, for a moment not thinking about Mabel. So she decided to correct that.

“All right, put your tongue to good use,” she said, crawling forward and sitting on Bill's face.

He was startled, seizing her calves, but then he settled, taking in the view of her perched above him. Then he grinned and opened his mouth, tongue sliding along her wet pussy before pressing inside, and his lips moved against her labia as he suckled.

“Nngh, Bill...” She leaned more weight on him, gripping his hair in one hand. He put more pressure on her, mouthing more quickly as he continued to lap at the sensitive skin. Pleasure bloomed in her core, legs shaking already, a tingling hot sensation overtaking her lower body. She wasn't going to last long at all like this, still worked up from earlier, but that was fine, she supposed... this was amazing. “You feel so great,” she told him, appealing to his praise kink. “And you look good too, eating me out while my brother fucks you, you're so twisted.”

Bill moaned against her. She answered with a soft moan too. “I love it though,” she continued. “This is perfect for you, really. Do you like it? Do you like giving in to us mortals, letting us use you? You seem to, you're so into this, listen to those noises you're making, you're such a slut.”

“Mabel!” Dipper admonished.

But Bill didn't deny it. He was so into this, both the way Mabel rode his face and spoke so boldly, and the way Dipper rode his cock... both their own pleasures, and he loved both of them. He wanted to reward the two. So he thrust his hips harder into Dipper, and added a few kisses to Mabel's pussy before giving long, slow licks, getting both twins to orgasm nearly at once. Mabel was first, and as Bill retracted his tongue, he felt Dipper grind down on him, liquid hitting his stomach a few moments later.

“So good,” Bill sighed blissfully, once Mabel had moved back to sitting on his chest again. He petted both of them. “I still haven't had my second orgasm, though.”

“We can fix that,” she assured him. She nodded to Dipper.

Much more sure of himself now, Dipper got off Bill's dick and moved between his legs, separating them and draping them around his waist.

Wait a moment. Bill lifted his head to look at him. “Are you-”

Dipper slammed into him. He was rough, aggressive, and Bill cried out his name in ecstasy.

The human paused, misunderstanding the cry. “L-lord, er, Bill, did that hurt?”

“I don't feel pain, that is fucking _amazing_. Fuck me, Dipper! It's about time you got the balls to do this!” Bill's head dropped back, and his back arched. He was so attractive, and Dipper's mouth went dry looking at him. He began moving, soon finding the best angle and using it. Bill was soon writhing under him, grinding into his thrusts, cock hard and rubbing into Dipper's stomach.

Mabel was exhausted, but she still had one more crazy idea. This would be a bit of a squeeze, but... she faced Dipper, grasping Bill's hard cock and sliding it into herself. She had to press herself firmly up against her brother to do this, but when she slid her arms around him, it felt more than right. His face buried against her neck, he was breathing hard, shoulders shaking, whimpering with pleasure. And Bill was making the loudest noises she's ever heard him make, and moaning their names, even begging. Yes, _begging_.

“Fuck, you two are good, nn please keep going, harder, gh... Dipper, scratch my thighs, and Mabel, grind on me, oh fuck, make me your bitch. Hhn...” Bill's eyes were screwed shut, two hands clutching his hair, middle pair gripping the sheets, and the last two on his partners. One hand helping balance Mabel, the other hand supported Dipper. And they were working him so good, he was getting closer, just a little more...

Mabel pressed her chest harder to Dipper's and lifted his chin, kissing him deeply. She bounced a little more energetically on Bill's cock, and it all got to be too much even for the god.

He wasn't exactly gentle in pushing Mabel off him, but she got the message and immediately moved to the side as he came, the cum instead splattering against his own stomach, a little bit hitting Dipper. He gasped desperately, legs squeezing Dipper, before feeling the human lose it and come in him.

“Fuck,” Bill sighed, body unwinding and slumping down against the covers. “You two... shit.”

Dipper pulled out of him and dropped his legs, and Mabel laid down next to him, stroking his hair. “How do you feel?”

“I feel... wonderful. You guys were so good, especially when you took over, I just... loved it.” Bill motioned to Dipper, who cautiously moved closer. He was tugged down to lay next to the god too. “Dipper, it's about damn time you did that. You've been way too submissive, and don't get me wrong, I love that sometimes. But I've been wanting you to dominate me. Thank you for finally doing it.”

“Oh. You're welcome.”

Bill kissed him, and then turned his head to kiss Mabel. “Awesome, both of you. Thank you so much. And the way you two got used to each other... oh man, I loved that. You really let go of those dumb human taboos, huh?”

“I guess so,” Mabel admitted.

“I'm just lucky to have such a hot sister,” Dipper said.

She smacked his arm lightly. “Not as lucky as I am to have such a sexy brother.”

“I love you, Mabes.”

“Love you too, Dip.”

“All right, wow, I definitely need some rest after all this,” Bill said. A snap of his fingers, and all their fluids were gone. “There, nice and clean. We'll still take a bath tomorrow of course. Sound good to you?”

They agreed, and Bill wrapped his arms around them, humming as both cuddled in close to him, their own arms draping around him. The trio softly exchanged kisses and goodnights before dropping off to sleep. Bill stayed awake longer than them, just enjoying how comfortable it felt laying with them, watching the dying candlelight flicker and cast soft blue light on them. Then he put out the candles with a thought, and closed his eyes. This was a night he won't soon forget.


End file.
